test_urllib2net fails in Python-3.13.11

[zuhu2195]

Bug report

Bug description:

======================================================================
ERROR: test_ftp_basic (test.test_urllib2net.TimeoutTest.test_ftp_basic)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/root/mohammed/python/Python-3.13.11/Lib/test/test_urllib2net.py", line 384, in test_ftp_basic
    self.assertIsNone(u.fp.fp.raw._sock.gettimeout())
                      ^^^^^^^
AttributeError: '_io.BufferedReader' object has no attribute 'fp'

======================================================================
ERROR: test_ftp_default_timeout (test.test_urllib2net.TimeoutTest.test_ftp_default_timeout)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/root/mohammed/python/Python-3.13.11/Lib/test/test_urllib2net.py", line 395, in test_ftp_default_timeout
    self.assertEqual(u.fp.fp.raw._sock.gettimeout(), 60)
                     ^^^^^^^
AttributeError: '_io.BufferedReader' object has no attribute 'fp'

======================================================================
ERROR: test_ftp_no_timeout (test.test_urllib2net.TimeoutTest.test_ftp_no_timeout)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/root/mohammed/python/Python-3.13.11/Lib/test/test_urllib2net.py", line 407, in test_ftp_no_timeout
    self.assertIsNone(u.fp.fp.raw._sock.gettimeout())
                      ^^^^^^^
AttributeError: '_io.BufferedReader' object has no attribute 'fp'

======================================================================
ERROR: test_ftp_timeout (test.test_urllib2net.TimeoutTest.test_ftp_timeout)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/root/mohammed/python/Python-3.13.11/Lib/test/test_urllib2net.py", line 414, in test_ftp_timeout
    self.assertEqual(u.fp.fp.raw._sock.gettimeout(), 60)
                     ^^^^^^^
AttributeError: '_io.BufferedReader' object has no attribute 'fp'

----------------------------------------------------------------------
Ran 16 tests in 31.503s

FAILED (errors=4, skipped=1)
test test_urllib2net failed
0:00:31 load avg: 2.49 [1/1/1] test_urllib2net failed (4 errors) in 31.7 sec

== Tests result: FAILURE ==

1 test failed:
    test_urllib2net

Total duration: 31.7 sec
Total tests: run=16 skipped=1
Total test files: run=1/1 failed=1
Result: FAILURE

I have built Python-3.13.11 from source and ran the test test_urllib2net in Linux ubuntu 6.8.0-53-generic. The test seems to fail because of typo in accessing fp from a HTTPResponse object. I have created a PR for the same

#143506

If this is a valid issue please merge the same.

CPython versions tested on:

3.13

Operating systems tested on:

Linux

Linked PRs

• gh-143507: Fix test in test_urllib2net #143506

[cocolato]

I think we should find the reason why _urlopen_with_retry return the _io.BufferedReader object, rather than change the assert.

[johnslavik]

+1.

What I can surely tell is that this isn't a typo.

The test is passing on my side, and the u looks like <addinfourl at 139887052771904 whose fp = <addclosehook at 139887052770848 whose fp = <_io.BufferedReader name=4>>>. Can you print u on your side and show us?

[zuhu2195]

In my case the u printed for test.test_urllib2net.TimeoutTest.test_ftp_basic is as follows,

-> breakpoint()
(Pdb) print(u)
<http.client.HTTPResponse object at 0x76e9b0507b60>
(Pdb)

[a12k]

I tried hard but can't replicate this test failure on clean builds of main or the 3.13.11 branch on either my local MacOS, or Debian.

[zuhu2195]

I debugged this further, seems like variable u is getting resolved to http.client.HTTPResponse only when proxies are set. when no proxies are set the test passes saying

skipped "Resource 'ftp://www.pythontest.net/' is not available"

Is this skipped message expected? or the test has to pass without this message?

The same skipped message is seen on MacOS as well.

[a12k]

No, a "skipped" test is an "untested" test. So, it never ran. socket_helper.transient_internet will typically skip the test if it can't access the resource for various reasons. Since that's FTP, one possibility is that port 21 (or higher ports for post-FTP initialization data transfer) is blocked on your network, so because the test cannot access that URL, the suite skips it.

You mentioned proxies. If you have a proxy, it's possible (especially HTTP proxy) that it's sending the FTP request over the proxy, which wraps the connection in additional layers to handle the tunneling, so when you try to access u.fp.fp.raw the urllib tests fail because the structure is different.

I would be really interested in seeing a repro though if you end up getting this working, but my sense is that this has something to do with your local network setup rather than a bug somewhere.

[zuhu2195]

Can the test case be modified to accommodate proxy setting?